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Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Pleistocene Mammals From The South Sulphur River, Hunt County, Texas, Leo Carson Davis, Kenneth M. Ball

Journal of the Arkansas Academy of Science

Preliminary collecting and excavating along the South Sulphur River has produced a diverse list of fossil mammals. The pampathere, Holmesina septentrionalis, and the large armadillo, Dasypus bellus, with their southern affinities from the extinct megafauna, were found in association with Microtus pennsylvanicus, which has a northern distribution at present. This combination of species argues for climatic conditions and biotic communities during the Pleistocene that have no modern counterparts.

Double Tuned Cosine Coil For Nmr Imaging/Microscopy, Roger M. Hawk, Rao P. Gullapalli, Dikoma P. Shungu

Journal of the Arkansas Academy of Science

The fabrication of a cosine coil having unevenly distributed struts is detailed. Placing the struts in such a manner enables a standing wave at the desired frequency and, hence, only one resonance frequency is obtained. This study details the fabrication of a cosine coil tuned to the LJ-7 frequency (77.76 MHz) and then double-tuned to the H-1 frequency (200.1 MHz) when operated at 4.7 Tesla. Double-tuning is attained by placing an LC trap in series with a capacitor used to single-tune the coil. Also, a method is suggested by which a cosine coil can be broadbanded in the lower frequency …

Farm Nutrient Management, William O. Thom

Soil Science News and Views

Nutrient management is becoming a buzz word in today's vocabulary of crop and livestock production. In the past it was applied to efficient management of all nutrient sources used for crop production. More recently it is being used to account for all nutrients used for crop production that are brought onto the farm, removed from the farm in crop and animal products, and reallocated within the farm unit. Nitrogen, phosphorus, and potassium are the nutrients of concern with nitrogen and phosphorus being most important.

An Object-Oriented Learning/Design Support Environment, Fillia Makedon, Julie C. Jumes, Jill P. David

Computer Science Technical Reports

We present an object-oriented experimental learning and design support environment, call AVT, for an Algorithm Visualization Tool, implemented in Digitalk's Smalltalk/V1 on a Macintosh II2, AVT provides a domain- independent visualization tool, an exploratory learning environment, and an experimental heuristic design environment. Algorithm visualization is the exploration of ways to visualize intuitively the computational behavior of an algorithm using multiple views, some of which are visual in the graphical sense [2,4]. AVT employs other views (combining text and graphics) to explain the problem, the strategy, the heuristics, and the reasoning process behind the solutions. User interaction in AVT includes not …

Littoral And Limnetic Zooplankton Communities In Lake Mead, Nevada-Arizona, Usa, Patrick J. Sollberger, Larry J. Paulson

Publications (WR)

Zooplankton were collected from adjacent littoral and limnetic sites in Lake Mead, Nevada-Arizona, USA. Limnetic species dominated both littoral and limnetic zooplankton communities; littoral species rarely exceeded 2% of monthly total zooplankton densities. Low species richness of littoral taxa and high similarity in species composition between littoral and limnetic habitats appeared to result from uniform horizontal physical and chemical environments, due to horizontal mixing, and from the absence aquatic macrophytes. Significant differences in spatial distribution occurred in phytoplankton biomass, total zooplankton density, and fish "abundances; highest concentrations of these factors occurred nearest an inflow high in nutrients and progressively declined …

The Diet And Feeding Habits Of The Southern Stingray, Dasyatis Americana, In Tropical Shallow Marine Habitats, David S. Gilliam

HCNSO Student Theses and Dissertations

The diet and feeding habits of the southern stingray, Dasyatis americana, were investigated through aerial surveys, land-based observations, and quantitative analysis of stomach contents. The field research was conducted in the Exuma Cays Land and Sea Park, central Bahamas. Systematic aerial surveys and the land-based observations were made to determine population density and feeding periodicity in terms of time or tidal phase. In August, 1989, systematic surveys were flown over two cays in the Park; a 12 km² area around Waderick Wells Cay and a 21km² area around Shroud Cay. Both survey areas were flown three times …

Winter 1991, Nsu Oceanographic Center

Currents

No abstract provided.

Spring 1991, Nsu Oceanographic Center

Currents

No abstract provided.

Summer 1991, Nsu Oceanographic Center

Currents

No abstract provided.

Fall 1991, Nsu Oceanographic Center

Currents

No abstract provided.

Curriculum-Oriented Cai Based On Instructional Technology To Be Used For Teaching Secondary School Students Introductory Library Skills, Theresa K. Toohil

CCAC Theses and Dissertations

In 1990, the New York State Education Department presented a syllabus that required the teaching of curriculum-oriented library skills and suggested the use of computers to be integrated with the teaching of these skills whenever possible. Schools in New York State are now trying to implement the suggestions in the syllabus. Many authors of educational articles have written at length concerning the incorporation of computer-assisted instruction (CAl) into the classroom, but clear directions have not been provided in the literature for the design or implementation of the necessary software.

The purpose of this study was to design a program based …

A Meta-Analysis Of Learner Control In Computer-Based Learning Environments, June A. Parsons

CCAC Theses and Dissertations

The objective of this meta-analysis was to integrate the results of a collection of primary research studies on learner control of computer-based environments. The scope for the meta-analysis was limited to inquiry on different learner-control models and their effect on student achievement as represented by posttest scores. Three specific research questions were defined:

1. What are the characteristics of the body of learner-control research which has examined the effect on achievement of learner control?
2. Is there a difference in the achievement of students who are provided with learner control and students who are provided with other control models?
3. Do specific moderator …

Recycling: Nature's Way, Joan Bray Ph.D, David Wallace

Environmental Education Resources

Edited by Teri Rosen.

This booklet is an overview of natural cycles such as the carbon cycle, nitrogen cycle, phosphorous cycle, and the water cycle. In addition, it discusses the impact humans have had on each of these cycles and it's effect on global warming and other climate changes.

Florida's Water Resources, Armalee Feegan B.A., David Wallace

Environmental Education Resources

Edited by Joan Bray and Teri Rosen. Northeast Florida Institute for Science, Mathematics and Computer Education.

This booklet is an overview of Florida's water resources such as groundwater, aquifers, rivers, springs, and other bodies of water. It also discusses management, problems with pollution, and water conservation.

Barrier Islands, Felicia West Ed.D., David Wallace

Environmental Education Resources

Edited by Joan Bray and Teri Rosen.

This booklet is an overview on the formation, structure, and role that barrier islands, dunes, barrier flats, and salt marshes play in the environment and water ecosystems. In addition, it explains the need to protect them and conserve these features.

Drop-Box Technique For Quantitative Sampling Of Macrofauna And Aquatic Plants At Restored And Natural Wetlands, J. Douglas Oliver, Andrew J. Leslie, William M. Bartodziej

Faculty Publications and Presentations

No abstract provided.

Potential Effects Of Climate Change On Milk Production And Conception Rate In Dairy Cattle In The United States And Western Europe, Peggy Lea Klinedinst

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders

Journal of the Department of Agriculture, Western Australia, Series 4

Native vegetation in the Western Australian wheatbelt now persists mostly in small areas that remained uncleared for various reasons. (See 'Remnant vegetation on farms is a valuable resource' on page 43.) On their own, most of these remnant areas are difficult to manage, and too small to retain viable populations of many of the birds and other animals found in the wheatbelt. These patches of vegetation can be linked by wildlife corridors, which may increase the ability of the wildlife to move about and persist in the area

The Tammin Alcoa Landcare Education Centre, Department Of Agriculture And Food, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

The town is home of the Tanimin Alcoa Landcare Education Centre. This is an ambitious concept by the Shire of Tammin and the Tammin Action Group to use the whole shire to demonstrate land conservation practices on farms, and to show urban and other communities what Western Australia's farmers are doing to conserve the land and practise sustainable agriculture.

The Effect Of Age Misreporting In China On The Calculation Of Mortality Rates At Very High Ages, Ansley J. Coale, Shaomin Li

Management Faculty Publications

When mortality rates by age are calculated from recorded deaths and enumerated populations, rates at higher ages are typically in error because of misstated ages. Mortality rates for China in 1981 have been calculated from the number of deaths in 1981 in each household recorded in the 1982 census, and from the census population back-projected one year. Because age was determined from date of birth, and because persons of the Chinese culture have very precise knowledge of date of birth, the mortality rates even at high ages should be unusually accurate. This expectation is fulfilled for most of China, but …

Lingin Derived Organic Matter In Georgia Coastal Waters, Mary Ann Moran, Lawrence R. Pomeroy, Edward S. Sheppard, Larry P. Atkinson

CCPO Publications

The importance of riverine- and saltmarsh-derived organic matter to the food web of Georgia coastal waters has been a focus of ecological research over the past thirty years. Studies based on energy budgets, carbon flux measurements, and stable isotope ratios have generally implicated marsh detritus as an important, although not always dominant, source of organic matter within the marshes and adjacent estuaries (Teal 1962, Odum and de la Cruz 1967, Haines 1977, Peterson and Howarth 1987). However, data on the contribution of exported marsh and riverine organic matter to productivity futher offshore, in continental shelf waters off the coast of …

Migration Patterns Of Double-Crested Cormorants East Of The Rocky Mountains, Richard A. Dolbeer

United States Department of Agriculture Wildlife Services: Staff Publications

The 5589 recovery records for Double-crested Cormorants (Phalacrocorax auritus) banded in North America from 1923 to 1988 were analyzed to determine migration patterns and the source of populations wintering in the lower Mississippi Valley and Gulf of Mexico coastal region. Autumn migration from areas north of latitude 42°N primarily occurred in October and November. Spring migration occurred mainly in April for birds >2 yr old and in May for birds <1 yr old. During summer,1-yr-old birds were recovered significantly farther from their natal colony than were older birds. Cormorants nesting in Canada and the northern United States from Alberta to the Gulf of St. Lawrence migrated in winter primarily to the southern United States between Texas and Florida. There was considerable mixing and overlap in winter of nesting populations from widely divergent areas. From 38 to 70% of the birds from Saskatchewan throughout the Great Lakes region were recovered in the lower Mississippi Valley as were 10% of the birds from such disparate areas as Alberta and the New England coast. There was little mixing of populations from east and west of the Rocky Mountains.

Population Size Of Pyrenean Troglobiont Coleopters (Speonomus Species) In A Cave In Belgium, Raymond Tercafs, Christine Brouwir

International Journal of Speleology

The population size of three troglobitic species of Speonomus (Coleoptera Bathysciinae) from the Pyrenees, intentionally introduced in 1969-1970 into the “Grotte de Ramioul” cave (Province of Liège, Belgium) has been studied using the mark-recapture technique. It has been shown that the three cave levels possess large Speonomus populations (upper network: 12,718; middle network: 13,902; lower network: 18,249 individuals) and that the superficial underground environment is also colonized, including the schist area. The most abundant species is Speonomus longicornis (relative frequency between 0.73 to 0.89). The two other species are present in the relative frequency between 0.04 and 0.23 for S. …

Evolution Of The Aeluroid Camivora: Viverrid Affinities Of The Miocene Camivoran Herpestides, Robert M. Hunt Jr.

Department of Earth and Atmospheric Sciences: Faculty Publications

Although the time of origin of viverrid and hyaenid carnivorans has not been clearly documented in the fossil record, their theater of evolution has long been established by a mid-Cenozoic fossil distribution entirely confined to the Old World. Recent examination of the basicranial morphology of important early aeluroid crania from Europe and Asia significantly alters earlier views of viverrid and hyaenid origins. The early Miocene carnivoran Herpestides antiquus, considered a potential ancestral hyaenid or herpestid in earlier studies, is identified as a true viverrid on the basis of a large sample of skulls of both juveniles and adults from …

Evolution Of The Aeluroid Camivora: Hyaenid Affinities Of The Miocene Camivoran Tungurictis Spocki From Inner Mongolia, Robert M. Hunt Jr., Nikos Solounias

Department of Earth and Atmospheric Sciences: Faculty Publications

Among the mammalian fossils discovered in were crania and mandibles of rare carnivorans, 1930 by the Central Asiatic Expedition of the including the first complete skulls of several Asian American Museum of Natural History (New York) mid-Miocene lineages. Most of these fossils came in the Tung Gur Formation of Inner Mongolia from a single locality termed Wolf Camp Quarry that produced, among other striking finds, a small fox-sized cranium referred to a new genus and species Tungurictis spocki Colbert 1939. Today this remains the only known cranium of Tungurictis yet discovered. Preparation and reinterpretation of the auditory region demonstrate that …

Reservoir Sedimentation Studies, D C. Boudurant, R H. Livesey

United States Army Corps of Engineers, Omaha District

It must be recognized that, when a reservoir is constructed on a stream, all or most of the sediment transported into the reservoir by the stream will be deposited there. With few exceptions, there is no practical method for reducing or eliminating the sediment inflow; thus it is necessary to anticipate and to provide for resulting problems. The major problem is, of course, the accumulative loss of storage capacity. Other items of importance include the distribution of the sediment with respect to various storage increments, the effect on the chemical or physical quality of the water, ecological effects, and the …

Potential Impacts Of Biomass Production In The United States On Biological Diversity, James H. Cook, Jan Beyea, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Biomass could be a renewable source of energy and chemicals that would not add CO₂ to the atmosphere. It will become economically competitive as its cost decreases relative to energy costs, and biotechnology is expected to accelerate this trend by increasing biomass productivity. Pressure to slow global warming may also make biomass more attractive. Substantial dependence on biomass would entail massive changes in land use, risking serious reductions in biodiversity through destruction of habitat for native species. Forests could be managed and harvested more intensively, and virtually all arable land unsuitable for high-value agriculture or silviculture might be used …

Radiation Risk Predictions For Space Station Freedom Orbits, Francis A. Cucinotta, William Atwell, Mark Weyland, Alva C. Hardy, John W. Wilson, Lawrence W. Townsend, Judy L. Shinn, Robert Katz

Robert Katz Publications

Risk-assessment calculations are presented for the preliminary proposed solar minimum and solar maximum orbits for Space Station Freedom (SSF). Integral linear energy transfer (LET) fluence spectra are calculated for the trapped-proton and galactic cosmic ray (GCR) environments. Organ-dose calculations are discussed using the Computerized Anatomical Man model. The cellular track model of Katz is applied to calculate cell survival, transformation, and mutation rates for various aluminum shields. Comparisons between relative biological effectiveness (RBE) and quality factors (QF) for SSF orbits are made, and fluence-dependent effects are discussed.

Reducing Computational Expense Of Ray-Tracing Using Surface Oriented Pre-Computation, Robert E. Rinker

UNF Graduate Theses and Dissertations

The technique of rendering a scene using the method of ray-tracing is known to produce excellent graphic quality, but is also generally computationally expensive. Most of this computation involves determining intersections between objects in the scene and ray projections. Previous work to reduce this expense has been directed towards ray oriented optimization techniques. This paper presents a different approach, one that bases pre-computation on the characteristics of the scene itself, making the results independent of the position of the observer. This means that the results of one pre-computation run can be applied to renderings of the scene from multiple view …